Fastener



Jan. 18,1944; lE KERN 2,339,412

FASTENER Filed Nov. 19. 1942 Patented Jan. 18, 1944 UNITED sTATss sari-:NT OFFICE FASTENER Emil Kern, Long Island City, N. Y., assignor to Acco Products, Inc., Long Island City, N. Y., a corporation f New York Application November 19, 1942, Serial No. 466,101

1o claims.V (C1. 2li- 153) The invention relates to filing devices and more particularly to a loose leaf fastener of the type including a base member having bendable prongs to extend through a stack of sheets and be interlocked with a separable compressor member of novel construction.

Prong fasteners including a base having bendable prongs and an associated compressor, such as is disclosed in Kline Patent No. 1,658,052, issued February 7, 1928, are best made vof thin sheet steel which is easily and inexpensively fabricated, and which retain their critical dimensions to insure proper functioning of their related movable parts so as to remain useful indefinitely. A critical metal shortage has occasioned the use of substitute materials as fibre, pressboard, cardboard, or the like. These materials are hard and are substantially shape retaining but, because they are porous, they tend to absorb moisture and frequently expand, contract or Warp suiciently to destroy the critical dimensions of the various compressor parts. As a result, any movable parts on a compressor made of such material will operate ineiciently and frequently bind to such an extent as to make them utterly useless for the purpose intended. The selection of substitute materials for the base member is restricted to those materials which may be bent or folded repeatedly without breaking and yet have sufficient toughness to resist tearing under normal conditions to use. Experience has shown that it is impossibleto properly retain prongs made of such substitute materials in their ultimate bent down or folded position by known types of metallic compressors.

Certain known types of fasteners made of cardboard, or like stock, lack practical means to retain the compressor tightly against the stack of sheets prior to, and in some instances after, bending and fastening of the prongs. This is because of the inherent tendency of the stack of sheets to resist compression. In known instances where such means may be provided, such as, for example, that shown in my companion application, Serial No, 466,100, filed of even date herewith, difliculty may be encountered in threading the prong through the compressor, particularly if the prong has become even slightly frayed at its end.

The present invention has for its aim the construction and organization of a pronged fastener which effectively overcomes the deciencies inherent in the fibre, pressboard, cardboard, etc., from which it may be made and certain undesirable characteristics of other known devices; and

one which is not expensive to manufacture but is very eicient in use.

It is therefore an object of the present invention to provide a fastener compressor embodying novel structural features to facilitate the threading of associated prongs therethrough and the movement of said prongs into a position to be wedged tightly in place so as to prevent unintentional separation of the fastener parts. v

Another object isto providea fastener compressor -of the character described with finger engaging means to facilitate its being shifted into binding-wedging engagement with associated prongs.

Another object is to provide a fastener compressor with integral wedge-naps suitably shaped to facilitate easy movement of associated prongs into position for cooperative engagement thereby.

Another object is to provide a reinforcedvcompressor having simple means to receive and bindingly and wedgingly co-act with an associated member so as to resist any forces tending to cause separation of the parts, and which may be easily and quickly assembled or disassembled.

VAnother object is to provide an apertured compressor having readily engaged means to bindingly and wedgingly co-act with associated prongs and novel means to retain the prongs in a folded down partially concealed position after assembly to increase the effectiveness of such an engagement.

The foregoing and such other objects of the invention as will appear hereinafter as the description proceeds will be more readily understood from a perusal of the following specification, in which reference is had to the accompanying drawing, wherein:

Fig. l is a perspective view of one embodiment of the improved fastener assembled on a file of papers, the le being partially broken away.

Fig. 2 is an enlarged transverse sectional lview taken on line 2-2 A-of Fig. 1.,

Fig. 3 is a central 'longitudinal sectional View of the fastener, showing the base in elevation and one prong partially disengaged.

Fig. 4 is a top plan view of the fastener showing the parts inthe relative positions illustrated in Fig. 3. y

Fig. 5 is a plan view similar to Fig. 4, showing the compressor in a transversely shifted position relative to the associated prongs.

Fig. 6'is a perspective view of a modified form of compressor, showing one prong engaged therewith.'

Like reference numerals are used herein to,

identify corresponding parts in the various embodiments disclosed.

Referring to the drawing and particularly to A Fig. l, the improved fastener is shown applied to a le folder including cover members II and I2 having a stack of sheets I3, to be bound arranged therebetween. The cover` members II and I2 usually are made of pressboard or the like and each may include a mounting strip I 4 hingedly connected thereto by means of flexible binding strips I5 whereby the cover members may be moved freely into open or closed positions to afford access to the fastener and bound sheets.

The fastener illustrated includes a base member I6, best shown in Fig. 3, and a compressor IT each of which may be formed of any substantially stiff sheet material 4such as fibre, press' board, cardboard, or the like. The basev I6 is formed of an elongated strip of such material and comprises an intermediate' body portion I8` having bendable prongs I9 at its ends` preferably of a Width substantially less 'than that of the intermediate portion. Longitudinal ribs 20 may be formed on the bottom face ofthe intermediate body portion I'8v to stiffenA it against longitudinal flexing; The base member is applied to the le folder by placing the intermediate body' portion I8 against the bottom face of the folder strip Il!V and extending the spaced prongs I9 through similarly spaced aligned' holes 2I in both strips andthe stack of sheets. When thus mounted. the free end' portions ofthe prongs-project upwardly beyond the top surface of the top strip I4 as shown. I

The compressor I1 preferably is-'f'ormed from a strip' of heavier stock'than the base member and isi-particularly designed to cooperate with the extending end portionsof'theprongs: Transversely spaced' offsets, preferably'l in the*V form of' longitudinal ribs 22, are providedv on the bottom face of compressor IiI to= reinforce said strip and to define a longitudinal invertedl channel 23 co-extensive with thellength of theV compressor. I'he ribs 22` areloc'atedclosely' adjacent to one longitudinaledge of4 the compressor, thereby providing one marginal ange 24 of'lesswidth than the otherl marginal flange 25.

Suitable openings 26, preferably in the form of' transverse slots, are providedin the compressor one adjacent each end Aand spacedA apart a distance substantially equal to thejs'pa'cing ofthe prongs- These openings, asbest vshown in Figs. 4 and 5, are located'in the marginal flange 25 and extend transversely inwardly through the adjacent rib 22. Their overall length and width is at least such as will freely admit 'the' extended endl portions of the prongs whenv the latter are threaded therethrough and the" compressor moved downwardly against 'the top face of the cover strip I4;

The inner end of each. slot26-terrninates' in a transverse-slit 21. The'seslits arespaiced apart substantially the" same distance as the prong spacing and they align: with theA longitudinally outer sidel edgeof the respective slots 26, as shown. The slits 2'Il are of a' length substantially equal to the width of the invertedch'annel 2&3v andV each communicates withV a longitudinally inwardly directed'slit 28 at each end to denne a substantially U-sllaped slit.' at. each compressor end.- The compressor portionsI partially surrounded by saidslits? constitute' flaps' 29. which normally lie substantially in the plane ofthe compressor. It` will l be'- noted; particularlyy upon reference to Figs. 4 and 5, that the corner of each ilap29 adjacent the slot 26 has been removed to increase the effective length of said slots and for a purpose to be better understood when the fastener operation is hereinafter explained.

It should be obvious at this time that, when the compressor is in the initial position shown in Fig. 5 with the prong` portions I9 extending through the openings 2S, it may be shifted transversely relative to said prongs to locate the prongs in the slits 21. The slits 2'! are necessarily of a width narrower than the thickness of the prong material, consequently movement of the prongs transversely therein deilects the flaps 29 and causes'them to flex upwardly slightly out of theplane of the compressor as best illustrated in Fig. 3. This ilexing of the naps 28 creates a binding-wedging action on the prongs and prevent-sV unintended movement of the compressor away from the face of the le. Cooperative engagementbetweenthecompressor and the prong permits the stack ofA sheets to be compressed tightly ain'iheldY prior t'o'nal securelnent of` the prong' ends.

After the compressor isthus'applie'd the extending end portions of the prongsare folded over inwardly towards'each other to overlie the respective flaps 29' (Fig. il and are retained in this position uponY being extended downwardly, through other compressor openings SI, into the inverted channel 2'3.- This folding' over of the prongA portions urges they flaps: 29 downwardlyV more tightly againstitheengaged. prongs thus increasingtheir wedging. action. Retention of the compressor is fur-thered by. the distortion 0r kinking ofthe prongsat'the flaps, asat- 32.

Finger engagement. of the compressor for effecting its transverse shifting is facilitated by upsetting suitable arcuate portions 33 and 34 on the respective marginal flanges 24 andy 25.

The fastener compressor illustrated in Fig. 6 is substantially like that form just described except that in this instance the medial compressor p0rtion 35 is elevated to provide an inverted channel for receiving the bent over ends ofthe prongs I9 after they are inserted through transverse openings 3l. Longitudinalspaced ribs 36 extend outwardly from the' ends of the raisedmedial portion 35 to dei-lne end channels 3l on the top face ofthe compressor for receiving the exposed por-v tions of'the bent over prongs and protect them against such inadvertentV4 engagement as might tend'to pull them out of the respective openings 3|; Inl this embodiment, eaCh'transl/elrse S101', 2E'

provided in the marginalwportion 25, extends through one of' the ribs 36 to connect with its respective transverse slit 21'.

Obviously the fastener herein described may be usedtobind sheetsin' a stack withoutA the use of' le folders. It should be evident also that the improved fastener is charac'terizedr by the absence' 'of any'rnanu'ally movable" locking' devices; such as slide'lat'ches, and consequently is-n'ot susceptiblefto being rendered ineffective shouldabsorption of' moisturev or other' causes result inf This-minimizes the binding effect of the naps and' permits*v the* prongs to* slide easily through the' compressor slits` 221.

Although the instant disclosure is concerned with several specific embodiments of a non-metallic fastening device, it should bev understood that this disclosure is by way of illustration only and not by way of limitation, and that the invention may be embodied in fasteners made wholly or in part from metal or may embody various modifications in minor details without departing from the spirit and scope of the appended claims.

I claim:

1. A fastener compressor comprising a flat strip of substantially stiff material, said strip having a substantially U-shaped slit adjacent each end to define flaps normally lying substantially in the plane of said strip, the intermediate portions of said U-shaped slit terminating at one end in an opening of a size to freely receive a prong of an associated base member threaded therethrough, said compressor being adapted to be shifted transversely relative to the prongs to carry the prongs out of the openings and into the complemental intermediate slit portions whereupon the iiaps are displaced and the compressor and prongs are held against separation by the binding-wedging action of said flaps, and means on the compressor adapted to retain the prongs bent down over said flaps.

2. A fastener compressor comprising a fiat strip of substantially stilT material, said strip having a substantially U-shaped slit adjacent each end each having its leg portions extending longitudinally inwardly towards the other to define 1ongitudinally opposed aps normally lying substantially in the plane of said strip and its intermediate portion terminating at one end in an opening of a size to freely receive a prong of an associated base member threaded therethrough, said compressor being adapted to be shifted transversely relative to the prongs to carry the prongs out of the openings and into the complemental intermediate slit portions whereupon the flaps are displaced and the compressor and prongs are held against separation by the binding-wedging action of said flaps, and means on the compressor adapted to retain the prongs bent down inwardly over said aps.

3. A fastener compressor comprising a flat strip of substantially stiff material having a longitudinal channel in its bottom face, said strip having a substantially U-shaped slit adjacent each end each having its leg portions extending longitudinally inwardly towards the other te define longitudinally opposed flaps normally lying substantially in the plane of said strip and its intermediate portion terminating at one end in an opening of a size to freely receive a prong of an associated base member threaded therethrough, said compressor being adapted to be shifted transversely relative to the prongs to carry the prongs out of the openings and into the complemental intermediate slit portions whereupon the flaps are displaced and the compressor and prongs are held against separation by the binding-wedging action of said iiaps, and means on the compressor adapted to retain the prongs bent down inwardly over said flaps.

4. A fastener compressor comprising a fiat strip of sheet material having spaced apart longitudinal reinforcing ribs on its bottom face, said strip having a substantially U-shaped slit adjacent each end to define longitudinally opposed iiaps normally lying substantially in the plane of said strip, the intermediate portions of said slits terminating at one end in an opening of a size to freely receive a prong of an associated base member threaded therethrough, the prong being relatively thick as compared to the width of the slit, said compressor being adapted to be shifted transversely relative to the prongs to carry the prongs out of the openings and into the complemental intermediate slit portions whereupon the flaps are flexed upwardly and the compressor and prongs are held against separation by the binding-wedging action of said flaps, and means on the compressor adapted to retain the prongs bent down over said iiaps.V

5. A fastener compressor comprising a flat strip of substantially stiff material having spaced apart longitudinal reinforcing ribs, said strip having a substantially U-shaped slit adjacent each end to define longitudinally opposed flaps normally lying substantially in the plane of said strip and its intermediate slit portion terminating at one end in an opening of a size to freely receive a prong of an associated base member threaded therethrough, said compressor being adapted to be shifted transversely relative to the prongs to carry the prongs out of the openings and into the oomplemental intermediate slit portions whereupon the iiaps are displaced and the compressor and prongs are held against separation by the binding-wedging action of said flaps, and means on the flaps to facilitate movement of the prongs into said slit portions.

' 6. lA fastener comprising a base having spaced bendable prongs arranged against one face of a stack of sheets with its prongs threaded through spaced holes in said stack, a compressor formed of a strip of material which is relatively wide as compared with the width of the prongs, a longitudinal channel in the bottom face of said strip, said channel being spaced closely adjacent one longitudinal edge of the strip and being of a width at least equal to the width of said prongs, the strip having a transverse slit at each end each terminating at one of its ends closely adjacent to the said longitudinal edge and at its other end in a transverse slot, longitudinal slits extending inwardly from each end of said transverse slits to define therewith iiaps, the slots being relatively wide as compared with the thickness of the prong material whereby the prongs may be threaded therethrough when the compressor is placed against the other face of said stack, said compressor being shiftable transversely to engage the prongs in the respective slits, and the prongs being bendable inwardly towards each otheragainst the top face of the compressor to urge the iiaps into binding-wedging engagement with said prongs at their bends.

7. A fastener comprising a base having spaced bendable prongs'arranged against one face of a stack of sheets with its prongs threaded through spaced holes in said stack, a compressor formed of a strip of material which is relatively wide as compared with the width of the prongs, the strip having a transverse slit at each end each terminating at one of its ends closely adjacent to one longitudinal edge of said strip and at its other end in a transverse slot, said transverse slits communicating with longitudinal slits eX- tending inwardly from each of their ends to dene therewith flaps, the slots being relatively wide as compared with the thickness of the prong material whereby the prongs may be threaded therethrough when the compressor is placed against the other `face of said stack, said compressor being shiftable transversely to engage the prongs in the respective slits, said engagement iiexing the flaps to cause them to bindingly engage and preventy withdrawal .or the: prongs longitudinally; V81A fastener. compressor. comprising a fiat strip of substantially stiff material having a longitudinal ychannel in itsibottom face terminating short of the endsiof saidstrip,fsaid strip having a substantially U-sh'aped slit-adjacent ea'ch of its endseach having its` leg portions extending lorrgitudinally inwardly towards thechannel to define longitudinally opposed flaps-normally lying substantially in the plane of said strip( and its intermediate slit portions terminating at one end in anr opening of a size tovfreely receivea prong havinga. thickness relatively greater than the width of the slit threaded therethrough, said compressor being adapted to be shifted. transversely relative tothe prongs 'to'carrythe prongs out of the openings and into the complemental intermediate slit portion whereupon-the flaps are flexed upwardly and the compressor and prongs are held against separation by the binding- Wedgingi action of saidflaps,` the channel having open ends. through whichthe prongs may be threaded to hold them bent down inwardly towards each other over the underlying flaps.

9. A fastener compressor comprising a flat strip of substantially stiffv material having allongitudinal channel extending inwardly from each end; said-strip having a-substa-ntially U-shaped slitl in the bottom wall of each: channel to define longitudinally opposed flaps normally lying substantially in` the. plane of said bottom WallA and. its intermediate slitportions terminating at one end in an opening of a size rto freely receiveay Yprong of. an associated base member threaded therethrough,A said compressor being adaptedl to be shifted transversely relative to the prongs to carry the prongs out of tlie'openingsl and into theV complemental intermediate slit portions whereupon theflaps are flexed'upwardly and the compressor and. prongs are held against separation by the binding-wedging action of said iiaps, and means on the compressor adapted to retain the prongs bent down into the channels over said flaps.

10. A fastener comprising a base having-spaced bendable prongs arranged against one face of a stack of sheets with its prongs threaded through spaced holes in said stack, a compressor formed of a strip of material having a transverse slit at each end terminating at one of its ends in an opening, said transverseV slits joiningl with longitudinal slits extending from each of their ends to--denetherewith iiaps; the openings being of such size as to-permit threading of the prongs therethrough freely when the compressor is placed against the other face of said stack, said compressor being shiftable transversely t0 engage the prongs in the respective transverse slits, and the prongs being bendable down against' the top. face of the compressor to overliel and urge the iiaps into binding-wedging engagement with said prongsat their bends.

EMIL KERN; 

